Low frequency magnetic fields less than approximately 10 kHz may be measured with small offset errors by integrated Hall probes. By implementing a spinning current technique, the Hall probes have low flicker noise and are highly linear versus magnetic field (below 400 mT flux density), and are free of hysteresis. By implementing a stress compensation technique, the Hall probes have low lifetime drifts of magnetic sensitivity. Due to the time discrete signal processing of a spinning current technique, the bandwidth of a typical Hall probe is limited to approximately 10 kHz.
High frequency magnetic fields may be measured by air coils. Air coils have low impedance and are highly linear versus magnetic field. For some applications, such as remote or contactless sensing of electric current via its magnetic field, there is considerable interest in magnetic field sensors for wide bandwidths from DC up to 100 kHz.
For these and other reasons, there is a need for the present invention.